The present invention pertains generally to construction of wood buildings, and more particularly to a tape that may be used to accurately measure the structural blocks that are placed between adjacent wall studs, roof rafters, ceiling joists, and floor joists.
Wood buildings are built by assembling individual studs, headers, rafters, etc. into walls, ceilings, floors, and roofs. All dimensions are set by the UBC (Uniform Building Code). Most floors, roofs, ceilings, and walls are built using two-by (2xc3x97) dimensional framing lumber. For example, 2 by 4 lumber may be used in walls, 2 by 12 lumber may be used in floors, and 2 by 8 lumber may be used in roofs. The UBC requires that these wall stud, floor joist, and roof rafter framing members be placed on 16 inch centers. This means that the centers of the boards must be 16 inches apart. Other centers are sometimes specified. For example, the UBC requires that truss roof framing members be placed on 24 inch centers.
Conventional tape measures typically contain marks at 16 inch intervals to assist in the placement of the framing members. The framing lumber is actually about 1xc2xd inches wide meaning that xc2xe inch of wood is on each side of the center line. This means that there will be about 14xc2xd inches of free space between the sides of adjacent framing members. Structural blocks are placed in this space to give integrity to the structure. An example of this is the placement of a block between two adjacent floor joists. The block keeps the joists in upright positions and keeps them from twisting on their nails. Blocks are also used in other ways such as for fire blocks, Freis blocks, pressure blocks, mid-span blocks, and diaphragm blocks.
The framing lumber is, however, typically wider than 1xc2xd inches due to the original cut, being bowed, or being swollen due to moisture. Also, exact placement of the centers of adjacent members at the specified distance is rarely perfect. Therefore, in practicality the actual distance between adjacent members will be less than 14xc2xd inches. Some tolerance in the lengths of the blocks is therefore desirable to allow them to fit into place between the framing members easily. The width of a standard 7xc2xc inch saw blade, which is about {fraction (3/32)} inches, can be used to create such a tolerance in the lengths of the blocks. A 2xc3x97 board is marked and cut at 14xc2xd inch intervals creating blocks that are slightly less that 14xc2xd inches long due to the width of the saw blade. Similarly, by measuring and cutting blocks at 22xc2xd inches, blocks are created which will fit between truss roof rafters that are routinely set on 24 inch centers.
The preferred method of making a block is to use a special saw fixture that has a table and a stop which is set to produce a 14{fraction (13/32)} inch long block. A long board is fed into the table until it abuts the stop. A block is then cut. This feeding and cutting process is repeated until the desired number of blocks have been produced.
However, the special saw fixture is often not available at a job site. The carpenter must then make the 14{fraction (13/32)} inch blocks by measuring and cutting them using hand tools including a tape measure, pencil, and square and power tools including a circular saw and blade. To do so, the carpenter measures a 14xc2xd inch interval on a long board and makes a block. The problem with this method of making one block at a time is that it is very tedious and time consuming. Or, the carpenter makes a pattern using one 14{fraction (13/32)} inch block and progressively marks a long board allowing for the width of the blade. The problem with the second method is inaccuracy. Each time the carpenter moves the pattern block down the length of the board, there is opportunity for measurement error. As a result, the second method typically produces blocks of inaccurate lengths that do not properly fit between the framing members.
Measuring tapes and framing tools are well known in the art. For example, U.S. Pat. No. 4,149,320 shows a measuring tape for manual measurement in the building construction industry. The measuring tape comprises a pressure-sensitive adhesive tape that may be placed upon a structural member as a template.
U.S. Pat. No. 4,367,590 illustrates a calibrated tape for use in constructing walls with vertical studs. The calibrated tape is capable of being separated into halves along a central portion thereof. The tape has indicia thereon which represent units of distance: each half of the tape has the same indicia as the other half The tape is secured to a pair of adjacent plates which are then used to form the upper and lower plates of a wall of the type having spaced, vertical studs secured to the plates.
U.S. Pat. No. 4,499,666 shows a framing layout tool which facilitates the accurate and quick layout of framing marking for a structure. A bi-directional measuring scale provides a means for measuring and marking the location of any size door or window opening.
U.S. Pat. No. 5,012,590 discloses a layout tape for use in positioning building materials, such as studs, joists, and rafters, in a building. The tape is left in place in the building upon completion. The layout tape preferably has an adhesive backing for mounting the tape at the point of use. Indicia on the tape indicate to a user the direction of layout, centers in desired multiples of unit lengths, and right/left material mounting positions in relation to such centers.
U.S. Pat. No. 5,129,153 comprises a structural member spacing tool for positioning adjacent structural members at a predetermined distance apart. During assembly, parallel, spaced apart support surfaces provide rigid support within a stud cavity between adjacent stud members.
U.S. Pat. No. 5,251,382 shows a measuring tape for quick determination of the center of a distance without requiring the calculation of the distance. The measuring tape includes two parallel edges and an ascending measuring scale along each edge printed on the same face of the tape and beginning at the same end of the tape. One of the scales has units calibrated to a conventional unit of length measurement. The second measuring scale has units calibrated to be exactly half the unit of the first scale.
U.S. Pat. No. 5,396,710 describes a generally U-shaped carpentry building tool which includes a reference plate member for placement on one or more building members. A first marking guide arm is connected at 90 degrees to one end of the reference plate member. A second marking guide arm is connected at 90 degrees to the other end of the reference plate member to form a generally U-shaped tool.
U.S. Pat. No. 5,913,586 depicts a tape measure on which the indicia allows the measurements to be read from either side. A centering strip is provided which gives fractional values corresponding to the primary indicia, thus allowing easy calculation of certain fractions of a given measurement.
The present invention is directed to a device for measuring wood blocks for use in the construction industry. The device may be utilized at a job site to measure and cut blocks more accurately than is possible using existing methods. The device comprises a tape measure which has marks at both 14xc2xd and 22xc2xd inch intervals. The device is placed on a long two-by board, registered against an end of the board, and then used to make marks on the board at the desired intervals. The board is then cut with a saw to create the blocks. The present invention allows the blocks to be made rapidly and, more importantly, avoids measurement errors.
In accordance with a preferred embodiment of the invention, a first set of spaced marks are longitudinally disposed on the surface of the tape at 14xc2xd inches apart. A second set of spaced marks are also longitudinally disposed on the surface of the tape at 22xc2xd inches apart.
In accordance with a preferred embodiment of the invention, the first and second sets of marks are the only marks disposed on the surface of the tape.
In accordance with another possible embodiment of the invention, conventional tape measure markings are also disposed on the surface of the tape.
Other features and advantages of the present invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of the invention.